1.
Building Microservices
Delhi Tech Meetup - 22/3/2017
{Prashant Parashar}
(Presentation slides used for the talk on “building micro-services”. Slides alone not a comprehensive material on the topic.)

2.
Why, when ?

3.
Two Pizza Teams
N(N-1)/2 is the number of conversation connections within a
team.

4.
Should I move to MicroServices?
What’s your traffic?
What’s your team size?
How complex is the system?

5.
Why?
Scale Platform Scale
Team scale

6.
Why?
Reuse Reusability
Replaceability
Focused Evolution

7.
“Don’t build microservices in a 5-people-startup!”

8.
Hows & whats of building

9.
Independent systems vs
micro-services
vs
Heterogeneous Interfaces
Federated Standards
Homogeneous Interfaces
Common Standards
Common design Language

10.
Identification
Clear separation of concerns, Isolation
Not just CRUD
Self-sufficient
Management vision

11.
Common design language
Interfaces, API language
Protocols
Security
Commons libraries
Other cross-cutting concerns
Clear architectural guidelines - Be pragmatic than ideal

12.
Architectural Concerns - Security
Simplistic - manage at firewall
Intermediate - inter-service tokens
Advanced: Identity service, encryption etc [Avoid till
you can]

13.
Architectural Concerns - Protocols
Create common libs for protocol standards [HTTP, Headers,
Marshaling protocols], connection pooling, failure
handling, logging etc
JSON, XML, Protobuf, all?
Provision for protocol/serialization versions! Always.

14.
Architectural Concerns - Context
Manage context across sync and async calls!
Context should contain:
❏ Unique source request Id
❏ User/actor id
❏ Caller service id
❏ Specific server instances
❏ Security/authorization info, if applicable

15.
Service Mess...Mesh

16.
Tip: Define upstream/downstream levels
Cross-cutting (even log, security etc)
User

17.
Aggregation
Do it closer to the user
UI Layers should have their own aggregation layer
Some duplication is okay

18.
Develop/Deploy/Test/Debug

19.
Testability
Automated tests is essential
Service level tests important
End-to-End tests?
Auto deploy with automated tests

20.
Debugging
Be verbose
Track call chain. Carry as much context as you can.

21.
Runtime Performance
Prepare for performance degradation of others
Use circuit breakers. Timeouts won’t help.
Isolation of problem is important. Design such.
Design for failure. Have product flag/alternative setup
Idempotent APIs help
Sync vs Async services - design for best & worst case

22.
one-size fits all

23.
Thanks!
www.prashantparashar.com
https://twitter.com/suco
der